Switch



SWITCH Filed May 25, 1942 Nov. 16, 1943.

INVENTOR I to .the operator.

Patented Nov. 16, 1943 UNITED STATES PATENT OFFICE swrron Axel E. Landerholm, New York, N. Y.

Application May 25, 1942, Serial No. 444,388

4 Claims.

This invention relates to a new and useful imresults without any material alterations intheir construction and with minimum expenditure of time or substantial increase in the cost of the switch when so modified.

Further and more specific objects, features, and advantages will more clearly appear from a consideration of the specification hereinafter shown especially when taken in connection with the accompanying drawing which forms part of the specification and illustrates a present preferred form which the invention may assume.

In types of switches to which the invention is especially adapted there is generally no snap device and consequently when the switch is in operation and it is suddenly thrown oif the parts are often liable to swing beyond the off or neutral position to another operative position. For instance, if the switch is connected to a motor and is in the forward position and then is suddenly snapped to the off position, the parts may wellswingbeyond the off position to the reverse position with the results that the motor may be damaged due to sudden reversal; damage to thework being done; blowing of fuses; injury Furthermore in these types of switches, ordinarily the operatingelement can be swung in' either direction and therefore inexpe-' rienced operators may swing it in the wrong direction. p v l n Broadly speaking and in the most general terms,the invention aims to eliminate all these detrimental possibilities and to make the switch as nearly fool proof as is humanly possible.

The switch generally comprises circuit making and. breaking parts usually enclosed within a casing and operated by the movement of a switch shaft in one direction or another from a neutral position. This operation of the shaft can be hand knob. This operating element has a neutral or off position, and two operative positions which may be an off position and a reverse position, these operative positions being disposed on opposite sides of the neutral or inoperative position of the operating element or shaft.

On the casing there are generally disposed stop members located adjacent to thetwo operative positions and adapted to engage a portion of the operating element'to prevent it from passing be yond the desired operative position.

The invention particularly concerns a detent plate associated with the operating shaft so as to be moved. when the shaft is moved. Preferably it is slipped on the operating arm in a snug manner so as to be snugly held thereon either against longitudinal or lateral movement thereon after being set in a desired position. The friction of the detent plate on its support is such as to achieve this result. This plate is provided with wings extending in opposite directions from the center of the plate and with a stop rib extending inwardly from the center toward the face of the adjacent switch casing. The detent plate has a normal position and two operative positions. In

the first or neutral position; the ends of the wings liein a plane inside the outer face of the stop members and closely adjacent thereto so that the operating arm can be swung but a slight distance in either direction from its off position when swung laterallyaround the support so that one of the wings is disposed closer to the adjacent face of the casing, then the other wing'is swung further away from the casing so as to clear the outer face of the adjacent stop and thus permit the switch to be moved in a given direction. By

swinging the wing plate in the opposite direction permission is thus achieved to move the switch in the opposite direction.

Thus it will be seen that there is associated and movable with a switch shaft, a detent element having three positions on its support, name- 'ly an inoperative or neutral position, and two This detent element has portions oppositely extending to points adjacent operative positions.

stop elements disposed on opposite sides of the neutral position of the operating shaft. When the shaft is in neutral position and the detent. is

in neutral position then the shaft cannot be movedin either direction. When the detent is in one operative position the switch can be moved 1 in one direction to an operative position and when the detent is in the other operative position then the switch can be moved to its other operative position.

Particulariy the detent plate has oppositely disposed wing portions which lie within the plane of the outer faces of the stop members when the detent is in neutral position. These wings slope from the center of the detent plate inwardly toward the surface of the casing in order to achieve this locational characteristic. When the plate is moved to swing one wing toward the casing more than usual, then the other wing is swung to clear the plane of the outer face of its adjacent stop, and vice versa.

The preferred form of the invention is shown applied to a standard type of switch in which the actual circuit making and breaking elements are disposed within a casing but are operated by an arm which has a neutral off position and which arm can be swung fro-m said neutral position in one direction to a forward position, and also can be swung from the neutral position in the opposite direction to a reverse position. In the normal operation of the switch there are stops disposed on each side of the operating arm to halt it in either of the operative positions.

. In the drawing,

Fig. 1 is a front elevation of the switch with the operating element in the off or neutral position;

Fig. 2 is a side view of the device with element in the same position;

Fig. 3 is a horizontal cross section taken on the line 33 of Fig. 1;

Fig. 4 is a view similar to Fig. 3, but with the novel detent member in one of its operative positions; and,

Fig. 5 is apartial front elevation of the device showing the operating element in one of its operative positions.

Although this particular type of switch is shown in the drawing, the invention can be the applied to any other type as long as it is one in which an operating shaft can be moved in either direction from a neutral position and has associated therewith a detent or stop element which when disposed in any one of a plurality of positions can limit the movement of the shaft in one direction or another.

Referring to the drawing in which one preferred form which the invention may assume is shown there is a casing I!) from which extends a shaft H on which within the casing the circuit changing members are mounted. This shaft is turned or oscillated by means of an arm or operating element l2 on the outer end of which is a hand knob 13.

In the position of the operating element I2 shown the switch is set in the neutral or "oif position but in the usual form can be swung to the left or to the right from this mid position to either a reverse or a forward position. Adjacent these operative positions are disposed'on the casing projecting members such as stops HI and I5 and these stops in the use ofthe switch prior to my invention would engage the shaft l2 and stop further movement of the operating element in either direction.

Associated with the operating shaft II and preferably, although not necessarily, mounted slideably but snugly on the operating element or arm I2 is a detent plate I6 having oppositely extending Wing or detent members I1 and I8, and

an inwardly extending longitudinal stop rib 19. When this detent plate is disposed in its so-called neutral position and the operating element is also disposed in its neutral position as shown in Figs. 1, 2, and 3, it is apparent that the handle l2 can not be moved hardly any distance in either direction from the neutral or ofl" position.

However, it will be easily seen that when the plate is pivoted around the arm 12 so as to swing either wing of the plate l6 toward the adjacent face of the casing [0, then as shown in Fig. 4, the other wing of the plate will be swung so as just barely to clear the top of the adjacent stop element, whereby it is obvious that the operating arm or element can be moved in one direction to one operative position but cannot be moved in the opposite direction to the other operative position.

It will be therefore observed that when the arm 12 and the plate l6 are both in their neutral positions, the arm cannot be moved in either direction because both wings of the plate 16 will meet their respective stops upon a slight movement of the arm [2 from its mid position in either direction. It will also be observed that by swinging the plate It from. its mid-position in either direction there will be created a corresponding limitation to the movement of the arm 12 in a given direction while permitting full and free movement in the opposite direction.

As shown in Fig. 3, particularly, the inner faces 20 of the wings of plate i6 are sloped inwardly slightly from the central portion of this plate and therefore their outer ends will lie, as seen, in a plane slightly within the outer face of the stop elements M and I5 and consequently the above mentioned blocking action will occur even when the plate It is in its mid position. How- 'ever, when the plate I5 is swung from its mid position to an operative position in either direction as seen in Fig. '4, the one end thus swung inwardly will even more be positioned to be blocked by the stop nearest to it while the other wing will be positioned as shown just to clear the stop member adjacent to it. Therefore, from Fig. 4, it will be seen that the wing plate is positioned so that the switch arm or operating element can be swung from its mid position to the left until the stop rib i9 abuts the stop element 14. During this movement to the left the fact that the wing I1 is just clear of the, stop M will keep the plate in its swung position because this practical abutment between the inner face of wing l1 and stop M will prevent the wing plate from swinging back to a neutral position.

It will also be seen that when the wing plate is swung on its arm l2 in the other direction from mid position then the switch arm I! can be oscillated in the opposite direction and a similar cooperative aotionof the'parts takes place.

Preferably there is disposed betweenthe knob l3 and the top of the wing plate l6 a felt washer 2| which will all the more create some friction to hold'the wing plate in any set position.

While the invention has been described in detail and with respect to a present preferred form thereof, it is not to be limited to such details and forms, since many changes and modifications may be made in the invention without departing from the spirit and scope of the invention in its broadest aspects. Hence it is desired to cover any and all forms and modifications of the invention which may come within the language or scope of any one or more of the appended claims.

I claim: 1. In a switch, an operating shaft,'an operating arm on said shaft, said arm having a neutral position and operative positions on opposite sides of the neutral position, stops on the switch adjacent the operative positions of the arm, a winged detent plate on the arm, said plate having neutral and operative positions, the wings of said plate adapted to engage the stops when the arm is moved in either direction from neutral if the plate is in its neutral position on the arm, a wing of the plate adapted to engage and be limited by one stop when the arm is moved in a given direction if the plate is in one of its operative positions.

2. In a switch, an operating shaft, an operating arm on said shaft, said arm having a neutral position and operative positions on opposite sides of the neutral position, stop members on the switch adjacent the operative positions of the arm, a winged detent plate on the arm, snugly fitting thereon and capable of being pivoted laterally thereon, oppositely extending detent wings on said plate, said wings sloping gradually toward the rear of the shaft from the center of the plate, the ends of said wings lying within the plane of the outer faces of said stop members when the detent plate is in its neutral position, one of said wings adapted to lie clear of the outer face of its adjacent stop member when the other wing member is moved inwardly nearer the rear end of the shaft, whereby the switch can be moved in one direction from neutral position but will tral position and operative positions on opposite sides of the neutral position, stop members on the switch adjacent the operative positions of the arm, a winged detent plate on the arm, snugly fitting thereon and capable of being pivoted laterally thereon, oppositely extending detent wings on said plate, said wings sloping gradually toward the rear of the shaft from the center of, the plate, the ends of the wings lying within the plane of the outer faces of the stop members when the detent plate is in its neutral position, one of said wings adapted to lie clear of the outer face of its adjacent stop member when the other wing member is moved inwardly nearer the rear end of the shaft, whereby the switch can be moved in one direction from neutral position but will be prevented from moving in the opposite direction from the neutral position, and an inwardly extending stop rib on the rear face of the detent plate and adapted to engage the respective stop members when the arm is moved to either of its operative positions.

4. In a switch, an operating arm adapted to swing in either direction from a neutral position, stop members on either side of the arm adjacent the operative positions thereof, a winged detent plate on said arm and adapted to be moved laterally thereon, said plate adapted to engage either stop member when the arm is moved in either direction from neutral position if the winged detent plate is in a neutral position, said detent plate adapted to engage only one stop member when the arm is moved from neutral position if the detent plate is laterally moved to one of its two operative positions thus permitting the arm to be swung only in a given direction to an operative position.

AXEL E. LANDERHOLM. 

